1. Field of the invention
The invention relates to an injection molding machine for the processing of plastics materials and other plasticizable substances having a protective cover for an injection nozzle.
2. Description of Related Art
The pamphlet xe2x80x9cSynergy, interaction of forcesxe2x80x9d by Netstal-Maschinen AG, 875 Nxc3xa4fels/Switzerland makes known an injection molding machine with this type of nozzle protection. The nozzle protection is displaceable in the direction of the axis of injection and runs on rails, which at the same time serve to enable the nozzle to be positioned on the stationary mold carrier. Guide braces are secured to the stationary mold carrier for this purpose. However, there is no protection against an attack from underneath. In addition, the cover is simply placed loosely in position, which means that vibrations can cause it to shake itself loose and, consequently, it does not provide any reliable protection.
The disposing of nozzle protection of this type is also known, where there is a lower, fixed section as well as an upper section, which can be removed from the lower section. The fixed arrangement of the nozzle protection makes it difficult to access the nozzle and the plasticizing cylinder.
A protective arrangement for a plastics material injection moulding machine having at least two injection moulding units is known in DE 1 234 975 B. As the usual axially displaceable protective arrangement can no longer cover the nozzle region properly in this case, adaptors are provided here for the extension of the braces, via which the second injection moulding unit, standing vertically, is supported. A two-part protection, which is disposed in a fixed manner in the axial direction, is disposed on these extension pieces. One of the two parts can certainly be pivoted out around a hinge-joint.
Proceeding from the state of the art, it is the object of the present invention to provide an injection molding machine with nozzle protection, which combines reliable protection with good accessibility.
This object is achieved through an injection molding machine for the processing of plastics materials and other plasticizable substances comprising: an injection mold assembly, accommodated between mold carriers in a mold clamping area, an injection molding unit for injecting the plasticizable substances into a central mold cavity of the injection mold assembly along an axis of injection, a plasticizing cylinder accommodated in the injection molding unit, an injection nozzle at an end of the plasticizing cylinder facing the injection mold assembly, said nozzle is adjacent an injection opening in the injection mold assembly during an injection process, a protective cover for covering the injection nozzle in a protective position during the injection process, said cover can be transferred from and into the protective position guided in an axial manner substantially parallel to the axis of injection, wherein the protective cover has a lower section, on which an upper section is mounted so as to be pivotable around a pivotal axis which is disposed substantially parallel relative to the axis of injection, and the lower section and the upper section are transferable together from and into the protective position.
The protective cover comprises an upper section and a lower section, which preferably surround the nozzle entirely. Where required, upper and lower section can be transferred out of and into the protective position together, which means that good accessibility is guaranteed, which can be increased even more by the upper section being pivotable relative to the lower section. This simplifies, for example, the removal of the plasticizable cylinder, it also being possible, at the same time, to remove the whole protective cover when work on the nozzle is to be carried out.